
/* 手机 */
.phone {
  width: 370px;
  height: 667px;
  background-color: #000;
  border-radius: 15px;
}

/* 音量指示器 */
.volume-indicator {
  position: relative;
  width: 40px;
  height: 180px;
  background-color: #333;
  border-radius: 10px;
  overflow: hidden;
  
  transition: width .3s, transform .3s;
}

.volume-indicator--mini {
  width: 10px;
  transform: translate(-10px, 0);
}

.volume-indicator__inner {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 120px;
  background-color: #fff;
  /* transition: height 50ms; */
}